Abstract: Calcium carbonate residue is a waste slag discharged from ammonium sulfate production with phosphogypsum as raw material.Its composition is subject to the ammonium sulfate production line，and the main mineral composition is calcium carbonate，whose dry basis content is at 72%~78%（mass fraction，same below），and the moisture content is at 15%~28%， and the two indexes always had a large fluctuation.Guizhou Wengfu Phosphate Fertilizer Plant using high solid/gas ratio suspended calcining-rapid cooling technology built a test preparation production line of active lime with calcium carbonate residue，and lime products will be used in environmental protection and building materials.According to the debugging experience of industrial test production line，the production process control points and control range of main technical parameters were summed up，and suggestions were also proposed for the optimization and improvement of the production line，so as to make a reference for the production practice.

Key words: calcium carbonate residue, high solid/gas ratio, suspension calcining, water content of raw material